TRANSGENIC TOBACCO PLANTS WHICH EXPRESS THE CHIA GENE FROM SERRATIA-MARCESCENS HAVE ENHANCED TOLERANCE TO RHIZOCTONIA-SOLANI

We have prepared independent lines of transgenic tobacco plants which express high levels of the Serratia marcescens ChiA protein intracellu larly or extracellularly (in glycosylated or unglycosylated forms). We have measured the susceptibility of these plants to Rhizoctonia solan i infection in greenhouse trials and in the field. Transgenic tobacco plants which constitutively express the S. marcescens ChiA protein exh ibit tolerance to the fungal pathogen R. solani. Disease tolerance is observed in transgenic tobacco plants which express the bacterial chit inase intra- or extracellularly. This is the first report to document disease reduction in the field in transgenic plants engineered for fun gal disease tolerance.